Method and device for perfecting folded paper boxes



L. E. LA BOMBARD AND M. H. S|DEBOTHAM.-

METHOD AND DEVICE FOR PERFE CTING FOLDED PAPER BOXES.

APPLICATION FILED FEB. 6. 1920.

Patented Jan. 31

2 SHEETS-SHEET I.

L. E. LA BOMBARD AND M. H. SIDEBOTHAM.

METHOD AND DEVICE FOR PERFECTING FOLDED PAPER BOXES.

APPLICATION FILED FEB. 6. I920.

- Patented Ja1i. 3l, 1922.

2 SHEETS-SHEET 2.

//V VENTURE in; 4 44M usually creased on four UNITED STATES PATENT orrlcE.

LEON E. LA BOMBABD, OF CHELS A, AND MELVIN H. SIDEBOTHAM, or CLIE'TOND LE, MASSACHUSETTS, ASSIGNORS '10 SPECIALTY AUTOMATIC MACHINE COMPANY, or CHELSEA, MASSACHUSETTS, A CORPORATION or MASSACHUSETTS.

METHOD AND DEVICE FOR PERFECTING FOLDED PAPER BOXES.-

Specification of Letters Patent.

Patented Jan. 31, 1922.

Application filed. February 6, 1920. Serial NO. 856,705.

To all whom it may concern:

Be'it known that we, LEON E. LA BOM- BARD, a citizen of the United States, and resident of Chelsea, in the county of Sufiolk,

State of Massachusetts, and MELVIN H. SIDE- BOTHAM, a citizen of the United States, and resident .of Cliftondale, in the county of Essex and State of Massachusetts, have invented certain new and useful Improvements in Methods and Devices for Perfecting Folded Paper Boxes, of which the following is a specification.

This invention relates to the manufacture of paper boxes of the type sometimes referred to as cartons which consist of blanks parallel lines and folded on two of said lines to bring the side margins of the blanks into overlapping relationship, the contacting surfaces of the overlapping portions being secured together by suitable adhesive material generically re-' the bodies of the blanks, glue being used to secure overlapping margins of said side portions together. Cooperating with v these folding belts are stationary members located to ensure folding on two of the crease lines of the blanks. In all such machines the folding action begins at the front ends of the blanksand terminates at their rear ends, this bein due to the forward travel of the blanks. lhe result is that the inward folding pressure, beginning at the front end of a blank, tends to laterally compress that end before completion of the folding is effected and final compression occurs. The result is a tendency to produce boxes which are slightly wider at their rear ends than at their front ends, as illustrated in a somewhat exa'ggerated manner in Figure 8 of the drawings. A misshapen box of such form is difficult to close after it has been set up for use and filled, because its end flaps can not be properly folded and tucked in. When such a box is to receive close fitting contents such as a bottle or a slightly smaller filled carton, some difficulty is experienced in insorting such contents.

It'may be Stated here however that when I boxes of perfect shape are required it has not produced satisfactory results, largely for the reason that if any portion of a passing box was wide enough to result in the side rails causing any collapsing pressure there on, the friction was so great that the means employed for moving the boxes was liable to send such box askew and result in choking the machine. The object ofthe' present invention is to provide flat folded boxes of uniform width or with Straight parallel folded edges from end to end even when made of quite inexpensive material, and we attain this object by so acting on the folded blanks before the glue sets, and while it is still in a condition to permit a sliding movement of one overlapping margin upon the other, that those portions will be straightened into proper super-position and the folded edges made parallel.

While the treatment referred to might be performed manually, it is obvious that in order to so treat the boxes issuing from a folding machine atthe high rate of speed of which such machines are capable, automatic mechanism for truing or straightening the boxes as they issue from a folding machine is desirable. In the accompanying drawings we illustrate an embodiment of the invention in its mechanical aspect,'but we do not limit ourselves to the mechanism so shown since we believe that we are the first to treat the folded blanks as above described, either manually or by mechanical devices. Therefore we maintain that our invention consists broadly in so actin upon or treating flat folded blanks, while t e glue is damp, as'to bring into true parallel relationship the edge portions of any tapering boxes.

Further features of the invention reside in the device or mechanism substantially as hereinafter described and claimed.

.Of the accompanying drawings Figures 1 and 2 are perspective views of the mechanism, looking from different positions, some portions being broken away in torted or tapered box which is objectionable for the reasons hereinbefore explained.

While the mechanism shown in Figures 1, 2 and 3 may be considered as an attachment to a folding machine, since the blanks are folded before reaching said mechanism, it is preferable to so construct the entire machine 1 that the frame bars 12 of the present mechanism are extensions or parts of the frame bars of the folding machine. Such folding machine may be either one of various specific kinds. For instance it may be similar to that in the La Bombard application filed February 20, 1918, Serial No. 218319, in which case the present mechanism would occupy a position between the ends of the belts of the folding mechanism and the small rolls 192 of that application which deliver the folded articles'to the belts 193, 194. In.

Figure 1 of the present drawings the deliveryiends of the belts of the folding machine from which the folded blanks issue to the present perfecting mechanism, are indicated at 13 and 14. The shafts 15, 16, and the gearing-17, 18, also belong to the folding machine proper.

Two transverse rods 19, 20, connect the frame bars 12, and two shafts 21, 22, are supported by bearing blocks mounted in the frame bars, said shafts having interineshg gears '23, 24, the latter being engaged by a suitably driven gear 25.

Mounted on the rod 19 and adjustable along it is a casting or web 26 having at one end two extensions 27 which laterally confine a pulle 28 splined on shaft 21. At the other end t e web 26 has two extensions 29 supporting a. pintle for an idle pulley 30. A belt 31 is mounted on the pulleys 28, 30, said belt also running over a tightener pul ley 32 carried by an arm 33 adjustablysecured to the web 26.

Below the web 26 and suitably mounted as by a bearing (not shown) on the lower rod 20, is a web 34 having extensions similar to those of web 26 and having pulleys 35, 36, the former being splined on shaft 22. A belt 38 is mounted on the pulleys 35, 36,

- and on a suitable tightener pulley (not shown). For reasons explained hereinafter the adjacent operative stretches of the two belts are not parallel, but are inclined-relatively to each other to present a space which tapers tolittle or nothing toward the end where the folded blanks leave said belts. The direction of travel is indicated. by an arrow in Figure 1. i I 1 Extending along opposite sides of the webs and their belts are two horizontal plates 39 each supported by a casting 40 mounted on rod 20 (Figs. '1 and 3) and laterally adjustable thereon. Each plate has a slot 41 in one end. Depending from the ends of each plate are stud shafts for two pulleys 42, 43, the shaft of the latter being adjustable along the slot 41; Mounted on each pair of pulleys 42, 43, is a belt 44, said pulleys being preferably flanged, as shown in Figures 3 and 5, to support the lower edges of the belts.

The belts 44 are driven at thesame speed as the belts 31, 38, by suitable means such as bevel gears 45 (Fig. 1) having splined connection with shaft ,22 and meshing with bevel gears 46 (Fig. 3) carried by the lower ends of the shafts of the pulleys 42. The inner stretches of the belts 44 do not pass straight from the pulleys 43 to the pulleys 42, but at intermediate points they pass over rolls 47 (Figs. 1, 2, 3 and 4) which cause the throat or passageway for the blanks to be less, laterally, where the belts pass said rolls, than elsewhere. In other words, the rolls 47 deflect the belts 44 toward each other. To enable the lateral width of this contracted. portion of the throat to be varied, and also to enable the positions of said contracted portions to be shifted toward either end of the throat, according to the length of folded boxes being operated upon, each roll 47 is mounted on a spindle or axle carried by a block 48 recessed as indicated in Figure 4, said recess fitting the inner edge of plate 39. By means of clamps or set screws 49 the blocks 48 and their rolls can be securedin position anywhere along the edges of the plates, and canbe set nearer toward or apart from each other as may be required to effect the desired results upon the folded boxes of any particular order that is being filled. 4

As'best shown in Figure 2, two shafts 50,

having small rolls 51, are mounted in bearmosses of which engages ear 25; The rolls 51 are slidable along their shafts so as to be in position to operate on the folded edges of the boxes issuing from the straightening throat. These two pairs of rolls '51 act as crease fiatteners and set the final form of the box by making the folded edges permanetly fiat guntil, later the box is to be opened or set up for filling). As they produce a result similar to that of a fiat iron run along a folded piece of cloth, they will be referred to hereinas ironing rolls.

While the mechanism as so far described will serve to perfect or straighten some folded boxes, we prefer," to also employ guides for the portions of the boxes near their'folded edges. As illustrated in the drawings each of said guides comprises an upper strip' 53 and a lower strip 54 suitably supported by the plates 39 and having their ends where the boxes enter curved apart (Fig. 3). The upper strip projects beyond the lower one toward the rolls 51 and is curved down to a point somewhat below the'plane of the upper edge of the lower strip.

The operation of the'machine is as follows Assuming that such a distorted box as shown in Figure 8 issues from the folding machine. It is immediately delivered, before'the glue sets (travelling at a speed nec" essary to produce, frequently, some 60,000 an hour) to the throat between the four belts 31, 38 and 44, 44.- They travel in the direction of the arrows, Figures 1, 3, 6 and 8. For the reason hereinbefore explained, all such mis-shapen boxes are narrower at their front advancing ends.

Of course the parts of this straightening or turning mechanism have been adjusted and set so that the distance between the opposing faces of the two belts 44 where they pass rolls 47 (Fig. 4) is equal to what the true' uniform width of the boxes should be. At this point the upper and lower belts 31, 38, are not close together. The lower face of the upper belt however is substantially in the plane of the lower edges of the two upper guide strips 53. Therefore when the wider portion of the box reaches this point, its sections a, b, will be horizontal and their overlapping parts, where the still wet or,

damp glue is located, are slid together. This, by a reflexv or leverage action, tends to spread or widen the*contracted end of the box as indicated in Figure 6. Said end which was contracted but is now widened is at this time under, or so nearly under, the depressed tips of the two upper guide strips '53 that it is laterally curved down as indicated in Figure 5, and'the belts 31, 38, which at this point are quite closetogether, press the glue-bearing areas together. As the box continues along, its folded edges below a predetermined limit.

w a; reach the nipof the ironing rolls 51 which render permanent the newly formed or alined edges, causing them to remainpermanently parallel.

At the point indicated in Figure 4 the belts 31, 38 are not so far apart but that the lower belt 38 acts as va support for the section 0 to prevent the crease which defines said section from section cl from yielding With said lower belt thus supporting sections 0, d the lateral collapsing effect is exerted to cause the before-described slip of wet-glued areas.

Having now described our invention, we claim:

1. The method of perfecting the shape of flat taper-folded boxes having overlapping glue-bearing portions, consisting in laterally contracting the wider ends of said boxes while the glue is soft.

2. The method of perfecting the shape of flat taper-folded boxes having overlapping glue-bearing portions, consisting in laterally contracting the wider ends of said boxes while the glu is soft, and then immediately exerting pressure on the overlapping portions.

3. The method of perfecting the shape of fiat taper-folded boxes having overlapping glue-bearing portions, consisting in laterally contracting the wider ends of said boxes while the glue is soft, and then immediately exerting pressure on the overlapping portions and ironing the re-shaped edge folds.

4. The method of making paper boxes of uniform transverse area at all lengthwise points, consisting in folding blanks to flat condition with overlapping glue-bearing edge portions, and then subjecting the, folded blanks to edgewise pressure before the glue is dry. 7

5. The method of making paper boxes of uniform transverse area at all lengthwise points, consisting in folding blanks to-flat condition with overlapping glue-bearing edge portions, and then exerting inward pressure progressively along the folded edge portion, then subjecting the folded.

blanks to edgewise pressure before the glue is dry, and immediately subjecting said overlappin edge portions to pressure.

8. Michanism for straightening taperfolded boxes, comprising a pair of belts for engaging the edge folds of the boxes, means for deflecting said belts toward each other at a point intermediate the ends of the belts, and means for supporting the boxes on their way between said belts.

9. Mechanism for straightening taperfolded boxes, comprising a pair of belts for enga ing the edge folds of the boxes, means for eflecting said belts toward each other at a point intermediate the ends of the belts, and upper and lower belts for guiding the horizontal travel of the boxes.

10. Mechanism for straighteningI taperfolded boxes, comprising a pair of elts for engaging the edge folds of the boxes, means for deflecting said belts toward each other at a point intermediate the ends of the belts, and a pair of belts between the first mentioned belts having their cooperating stretches at an acute angle to each other.

11. Mechanism for straightening taperfolded boxes, comprising a pair of belts for engaging the edge folds of the boxes, means for directing the boxes between said belts,

and adjustable deflectors for the belts.

12. Mechanism for straightening taperfolded boxes, comprising a pair of elts for engaging the edge folds of the boxes, means for directing the boxes between said belts,

and upper and lower stationary guides adjacent the inner faces of said belts.

13. Mechanism for straightening taperfolded boxes, comprising a pair of belts for engaging the edge folds of the boxes, me ans for directing the boxes between said'belts, and 'guides adjacent the inner faces of said belts, said guides being constructed and arranged to depress the marginal portions of 40 the boxes after they pass the location of said said throat, and means for depressing the marginal portions of the boxes after they pass said throat.

15. Mechanism for straightening taperfolded boxes,'c'omprising means for contracting the wider ends of the boxes while permitting the narrower ends to expand, and means for rendering permanent the new shape of the boxes.- v

16. Mechanism 'for straightening taperfolded boxes, comprisingv means for contracting the wider ends of the boxes while permitting the narrower ends to expand, and

means for ironing the foldedtedges of the boxes.

17. Mechanism for straightening taperfolded boxes, comprising means for contracting the wider ends of the boxes while permitting the narrower ends to expand, means for transversely curving the boxes after r adjacent to the inner faces of the side belts,

and ironing rolls in position to compress the folded edges of the boxes as they issue from said belts.

20. The method of straightening the gluelap joint of a creased and folded box, con-t sisting in sliding the members of said joint into parallelism with the creases of the box while the glue is soft.

In testimony whereof we have affixed our signatures.

f LEON E. LA BOMBARD.

MELVIN H. SIDEBOTHAM, 

